Bit.



Patented Nav. n, |902.

E. A.. COWLES.

BIT.

tion med Se )t 24.. 1901 i AUNITED STATES PATENT OFFICE.

EDWARD A. COWLES, OF FRANKLIN, PENNSYLVANIA.

SPECIFICATION formingpart of LettersPatent No. 713,067, dated November11, 1902.

Application tiled September 24,190l. Serial No. 76,397. (No model.)

To a/ZZ whom, it may concern.:

Be it known that I, EDWARD A. CowLns, av resident of Franklin,in thecounty of Venango and State of Pennsylvania, have invented cer- Y tainnew and useful Improvements in Bits; and I do hereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same.

My invention relates to improvements in'4 I bits, and more particularlyto bits for drilling through rock and earth, the object of the inventionbeing to provide an improved bit of this character which willeifectuallyut the rock and remove the core or broken particles.

With this object in View the invention con-l sists in certain novelfeatures of construction and combinations and arrangements of parts, aswill be more fully hereinafter described, and pointed out in the claims.

In the accompanying drawings, Figure l is a view in elevationillustrating one form ofV my invention. Fig. 2 is a view of itscutting., end, and Figs. 3, 4, 5, 6, 7, and 8 are views illustratingmodified forms of my invention.

l represents the main portion of the bit, provided at one end with asuitable shank 2 for its attachment to the drilling apparatus. The bitis of a general triangular shape in crosssection and made withlongitudinal Iiat depressions 3 on two sides and with three sharpradially-disposed cutting edges 4 at its end.v In the third side of thetriangular bit a deep longitudinal groove 5 is provided. This groove 5is widest at the outside of the bit and tapers to its inner portion,where it is made semicircular or concave and projects inward beyond thecenter of the bit, so as to form a cen-k tral receptacle for the core orbroken particles of stone and earth cut by the bit, and the outer faceof the extremes of the bitV are curved concentric with the centerthereof. This bit may be made four-sided instead of three, as shown inFigs. 3 and 4, the longitudinal groove 5 being provided in one of itssides, while in Figs. 7 and 8 I have shown a three-sided bit in `whichthe longitudinallydepressed sides'are made convex'instead ,of

flat. The sizes of these bits can be varied to `suit the uses to whichthey are put-as, for instance, in cutting into solid stone I employ amuch smaller bit, such as shown in Figs. 3, 4, 6, and 7, while inconstructing a well I employ a much larger bit, preferably of the styleshown in Figs. l and 2.

In Figs. 5, 6 I have shown a twist drill or bit. While a twist to thedrill or bit is not essential, it is in some cases desirable, as thelspiral form of the longitudinal groove due to the rotary motion of thedrill aids materially in the elevation and removal of the drillings.

Various other slight changes might be resorted to in the general formand arrangement of the several parts described without departing fromthe spirit and scope of my invention, and hence I would have itunderstood that I do not wish to limit myself to the precise details setforth, but consider myself at liberty to make such slight changes andalterations as fairly fall within the vspirit and scope of my invention.

IIaving fully described my invention, wha I claim as new, and desire tosecure by Letters Patent, is-

'1. A bit provided with a series of radial ribs having cutters at theirlower ends, said bit having a groove between two of said ribs extendingupwardly from the lower ends thereof, said groove having approximatelyparallel walls from end to end and having a depth to extend beyond thelongitudinal axis of the bit and form a core-receptacle having acontinuous lateral opening.

2. vA bit having several radially-disposed cutting edges and depressedsides with intergitudinal groove open at one side of the bitspecification in the presence of two subscrib and having a portioncoincident with the axis ing Witnesses.

of the bit to form a core-rece taaie, the other sides of the bit havingdepresions terminat- EDWARD A COWLES 5 ing at their lower ends betweenlthe said cut- Witnesses:

ting edges. BRYAN H. OsBoRNE,

In testimony whereof I have signed this WM. B. GRIFFEN.

